The occurrence of heartworm disease in cats in the United States has been steadily increasing over the last several years in certain areas. As a result, it is no longer considered a rare diagnosis.
The belief is that many cats that are coughing and were previously diagnosed with feline asthma, are in reality coughing because of heartworm disease. In a given area, the incidence of heartworm disease is thought to be 10-15% of the incidence of this disease in dogs.
If there is heartworm disease in dogs in your area, then there is a risk for the disease in cats in the area. There are preventative measures that can be taken to avoid heartworm disease in cats. Mosquitoes transmit heartworms. They inject baby heartworms called larvae. The larvae grow once inside the animal’s body and can cause different diseases depending on that animal’s response to the worm as it matures. It is believed that the baby worms cause the lion’s share of the disease.
The lungs of the cat are exquisitely sensitive to the presence of larvae. The lungs don’t like them and can set up an intense immune response around the little lower airways that acts like asthma. Much less frequent, but more immediately life threatening, is the disease caused by the adult worm. Adult worms live in the heart. The worms cause lots of irritation in the major vessels near the heart. Unfortunately, in some cats the first sign of heartworm disease is sudden death from a pulmonary embolism.
The symptoms of heartworm disease are coughing, vomiting, and difficulty breathing. Lots of other things can cause these signs as well, so have your vet test for them as well as for the heartworms.
If it is determined that your cat has heartworms, treatment is started to decrease the irritation in the vessels and lungs. There is a ton of coughing in cats. Using on of the heartworm preventatives can greatly decrease your cat’s risk of developing problems from the disease.
Several monthly preventative medications are available. Novartis' Interceptor Flavor Tabs (milbemycin oxime) are probably the best, as they contain no chemicals and are administered through an oral flavored pill. There are topical applications as well. Advantage Multi is a good flea product that is effective against heartworms and several other parasites.
Revolution is another. It may not be quite as good on adult fleas, but is good on heartworms. Another is an oral product called Heartguard™. If it is likely that your cat will be exposed to mosquitoes, then you might consider using one of these products. As times goes by, more will be learned about control of this disease.